Understanding Excel's 1900 serial number architecture, time fractions (1 hour = 1/24, 1 minute = 1/1440), date arithmetic (+1, +7, elapsed days), and volatility of TODAY() and NOW().
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Excel dates ko internally plain text ke bajay numeric serial numbers ke roop mein store karta hai.
01-Jan-1900. Har beeta hua din +1 add karta hai.
45000 = ek specific calendar date.1 Day = 1.012 Hours = 0.56 Hours = 0.251 Hour = 1 / 241 Minute = 1 / 14401 Second = 1 / 86400=A1 + 1 → Agle din ki date=A1 + 7 → 7 din baad ki date=B2 - A2 → Do dates ke beech elapsed calendar days| Function | Output | Recalculation Behavior |
|---|---|---|
=TODAY() | Current system date (e.g. 22-10-2026) | Workbook recalculate hone par update hota hai |
=NOW() | Current date aur time (e.g. 22-10-2026 18:30) | Workbook recalculate hone par update hota hai |
[!NOTE]
TODAY()aurNOW()volatile functions hain. Yeh static timestamp nahi banate aur har second chalne wali live watch nahi hain; yeh tab update hote hain jab workbook recalculate hoti hai ya F9 dabaya jata hai.
Practical Deadline Status Formula:
=IF(A2 < TODAY(), "Overdue", IF(A2 = TODAY(), "Due Today", "Upcoming"))
=TODAY() likhein aur Ctrl + 1 se dd-mmm-yyyy format karein.=DueDate - TODAY().Practice live Excel formulas directly in your browser. Real calculation verified by HyperFormula.
Calculate total revenue in cell D6 by summing all items in column D (cells D2 to D5).
Every formula you enter is evaluated by a real spreadsheet engine in your browser — results are not pre-computed.
| # | A | B | C | D |
|---|---|---|---|---|
| 1 | Product | Quantity | Unit Price | Total |
| 2 | Laptop | 5 | 45000 | 225000 |
| 3 | Mouse | 20 | 500 | 10000 |
| 4 | Keyboard | 15 | 1200 | 18000 |
| 5 | Monitor | 8 | 12500 | 100000 |
| 6 | Grand Total |
5 practical questions testing date serials, age calculations, working days, and shift scheduling formulas.
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Module 5: Excel Logical Functions — IF, AND, OR, NOT, IFS
Module 6: Excel Text Functions — Complete Mastery
Module 7: Excel Date & Time Functions
Module 8: Mathematical & Statistical Functions
Module 9: Conditional Functions & Criteria-Based Analysis
Module 10: Advanced Text & Modern Dynamic Arrays in Excel 365
Module 11: Date & Time Functions in Excel — Complete Reference
Module 12: Enterprise Text Manipulation & Encoding
Module 13: Advanced Logical Decision Systems & Custom Functions (LET, LAMBDA)
Module 14: Lookup & Reference Functions Masterclass
Module 15: Modern Dynamic Arrays & Spilling Engine
Module 16: Advanced Text Engineering & Master Data Cleaning
Module 17: Advanced Date, Time & Scheduling Intelligence
Module 18: Enterprise Decision Systems & Logical Modeling
Module 19: Comprehensive Math & Trigonometry Analytics
Module 20: Advanced Statistical Analytics & Predictive Forecasting
Module 21: Text Functions & String Engineering Masterclass
Module 22: Information Functions, Error Diagnostics & Data Auditing
Module 23: Advanced Statistical Analytics, Ranking & Regression Modeling
Module 24: Database Functions (D-Functions) & Criteria Engineering
Module 25: Financial Engineering, Loan Amortization & Investment Valuation
Module 26: Advanced Excel Tools, What-If Analysis & Optimization
Module 27: PivotTables & PivotCharts Masterclass
Module 28: Power Query — Data Cleaning, Transformation & Automation
Module 29: Power Pivot, Data Model & DAX Formulas
Module 30: Executive Dashboards, KPI Cards & Interactive Reporting
Module 31: Excel Automation with Macros, VBA Basics & Practical Projects
Module 32: Advanced Excel Automation: UserForms, Event-Driven VBA & Protection Systems
Module 33: Advanced VBA: Search, Update, Delete (CRUD), Database Connectivity & File I/O
Module 34: Enterprise VBA Architecture: Class Modules, Dictionaries & REST API Integration
Module 35: Advanced Excel VBA: Windows Integration, Office Automation & Enterprise Systems
Module 36: Real-World Business Automation: Inventory, Billing & MIS
Module 37: Enterprise Database Integration: Access, SQL Server, ADO & Transactions
Module 38: REST APIs, JSON Web Services & Cloud Integration
Module 39: Enterprise Automation Architecture, Synchronization & Deployment
Module 40: Enterprise Testing Frameworks, Automated QA & CI/CD Lifecycle
Module 41: Professional Excel Add-ins (.xlam), Ribbon UI XML Customization & Toolkits
Module 42: Modern Cloud Automation: Office Scripts (TypeScript) & Power Automate
Module 43: Python in Excel: Data Science, Pandas, Seaborn & Native AI Modeling
Module 44: Microsoft Copilot, Generative AI & Natural Language Formula Engineering
Module 45: Enterprise Financial Modeling, Cap Tables, DCF Valuation & M&A Analysis
Module 46: Supply Chain, Logistics & Operations Research in Excel
Module 47: HR Workforce Analytics, Payroll Engines & Performance Systems
Module 48: Advanced Visual Storytelling: Sunburst, Treemap, Waterfall & Dynamic Heatmaps
Module 49: Big Data in Excel: 100M+ Rows Optimization, VertiPaq & DAX Studio
Module 50: The Master Capstone: Building a Complete SaaS / Enterprise ERP in Excel